Driving mechanism for bicycles.



K. BROOKS. ,l DRIVING MECHANISM FR BICYCLES.

(Aplicmdn med am. 7, 1901.)

No. l7l,245. Patented Spt: 30, |902` MMM Wl TNE SSE S Tur. scams PETERSco. PHoYo'Llmcv. WASHINGYUN, uA c.

UNrTnD Taras- VKARMELL BROOKS, OF NEW YORK, N. Y.

DRIVING IVIECHANISNI FOR BICY'CLES.

SPECIFEGATION forming part of Letters Patent No. 710,245, datedSeptember 30, 1902.

Application led March 7, 1901. Serial No. 50,206. (No model.) i

To Y@ZZy whom. it may concern..-

Beit known that I, KARMELL BROOKS, a citizen of .the United States, anda resident of the city of New York, borough of Manhattan, in the countyand State of New York, have invented a new and Improved DrivingMechanism for Bicycles, of which the following is a full, clear, andexact description.

The purpose of the invention is. to loosely mount the front sprocket onthe crank-shaft of a bicycle and drive the said sprocket from the crankor pedal armof the crank or pedal shaft through a cushioned yet positiveconnection, the connectionfbetween said parts being such as will tend toobviate severe shock to the machine in operation and which will add toits lifetime, as well as contribute to the comfort 0f the rider.

The invention consists in the novel construction and combination of theseveral parts, as will be hereinafter fully set forth,

and pointed out in the claims.

Reference is to be had to the accompanying drawings, forming a part ofthis specification, in which similar characters of reference indicatecorresponding parts in all the figures.

Figure 1 is a longitudinal vertical section through the crank-hanger ofa bicycle and the front sprocket-wheel and a section through a drivingconnection between the front sprocket-wheel and a crank or pedal arm ofthe crank or pedal shaft. Fig. 2 is a section on the line 2 2 of Fig. 1.Fig. 3 is a section Qn the line 33 of Fig. 1; and Fig. 4 is a section onthe line 4 4 of Fig. 1, illustrating another manner of making theconnection between the crank-arm of the crank or pedal shaft and thefront sprocket-Wheel of the bicycle.`

A represents the crank-hanger, having the usual collar B to receive thecenter brace of the bicycle-frame, and C represents the crank or pedalshaft, having the usual crank or pedal arms D. The pedal or crank shaftO is held to turn by ball-bearings located Within the crank -hanger A,comprising cones 10, screwed upon or otherwise attached to thepedal-shaft, and ball-races 11, secured to the hanger, and through whichthe pedal-shaft is loosely passed.

end of the hanger A and a crank or pedal arm D. The front sprocket-wheelE is provided with one or with a series of openings 12, preferablycircular, as shown in Fig. 2. A sleeve 13 is fitted into one of theseopenings 12, and usually the sleeve extends beyoud opposite faces ofsaid front sprocketwheel, as is shown in Figs. 1 and 4. This sleeve issecured to the sprocket-wheel E by threads, solder, or by other means.

A tubular cushion 14 is fitted in the sleeve 13, and Vthe cushion, whichis preferably of rubber or a like material, is provided with a chamber14L between its outer and inner faces. The chamber 14, however, may bedispensed with, but when used tends to add to the elasticity ofthecushion.

A pin 15 is carried by the crank or pedal shaft C, and this pin ispassed through the central opening in the cushion, and the cushion 1-1-is held inplacein its sleeve 13 by wash- Aers 16 and 17, havingbearingagainstthe ends of the sleeve, the said washers being held inposition by a nut or like device, as is also shown in Figs. k1 and 4.

In Fig. l the pin 15 is shown as integral with the pedal-arm carryingit; but in Fig. 4 the pin is shown clamped upon the pedalarm, the clamp18 constituting a continuation of one end of the pin, and the sleeve 13is shown as a part of the wheel E. Under this construction it will beobserved that as the crank or pedal shaft revolves it communicatesmotion to the front sprocket-wheelE through one of the crank or pedalarms D, and it will bev further observed that While the connectionbetween the pedal-arm and the front sprocket-wheel is a positive one,yet the connection is cushioned to such an extent as will prevent asevere shock to the machine in 0peration and which will contribute tothe comfort of the rider.

The improved driving device is simple and effectiveand can be readilyapplied to any bicycle or similar machine.

Having thus described claim as new and desire to secure by LettersPatent- 1. In a driving mechanism for bicycles and similar machines, apedal-shaft and its crankarms one of the crank-arms being provided witha lateral projection, a driving-wheel my `invention, I'

IOO

loosely mounted on the said pedal-shaft, and a cushion connectionbetween the said driving-Wheeland the projection of the crankarm of thepedal-shaft, as set forth.

2. In a driving mechanism for bicycles and similar machines, a crank orpedal shaft and its crank or pedal arms, a front sprocketwheel looselymounted on the pedal or drive shaft adjacent to one of the said arms ofthe crank or pedal shaft and provided with an opening, and a lateralprojection on one of said arms of said crank or pedalshaft, Whichprojection is yieldingly held in the opening of the frontsprocket-Wheel, as set forth.

3. In a driving mechanism for bicycles and similar machines, a pedal orcrank shaft, crank or pedal arms carried by the shaft, a bearing forsaid crank or pedal shaft, a forward sprocket-Wheel loosely mounted onsaid shaft between its bearings and one ofits crank or pedal arms, thesaid Wheel being provided with an opening therein, a cushion locatedWithin said opening, a pin extending through the said cushion from thecrank-arm adjacent to the forward sprocket-Wheel,and means for holdingsaid pin in position in said for- I Ward sprocket-Wheel, as set forth.

et. In a driving mechanism for bicycles and like machines, thecombination with the drive or pedal shaft and its crank or pedal arms,of aforward sprocket-Wheel loosely mounted on said shaft, said Wheelbeing provided with an opening therein and a sleeve secured in saidopening, a tubular cushion located Within said sleeve, and a pin securedto one of the crank or pedal arms and passed through the said cushion,and means for retaining the pin in position in the sprocket-Wheel, asset forth.

5. In a driving mechanism for bicycles and like machines, thecombination with a drive or pedal shaft, and its crank or pedal' arm, ofa sprocket-Wheel loosely mounted on the said shaft and provided with anopening and an annular fiange surrounding the opening on each face ofthe Wheel, a cushion in said opening, a pin secured to the pedal-arm andpassing through the said cushion and provided witha nut on its end,andWashers on the pin and bearing against the iianges, around the openingin the wheel, as set forth.

ln testimony whereof I have signed my name to this specification in thepresence of two subscribing Witnesses.

KARMELL BROOKS.

Witnesses:

J. FRED. ACKER, EVERARD BOLTON MARSHALL.

